so with those new AGMs in the cabin. i needed a new AGM for the outboard starter. you shouldnt run acid and AGM on the same system. i got another steal at west marine on a brand new deep cycle AGM for $160.
long scary story short. i hooked up the 3rd battery. started the motor first push. and everything was awesome. i come into the cabin to celebrate with a beer. and i smell smoke. look back towards the new battery and both terminals have at least 3 inch flames shooting out of them! i panic for half a second and realize it is crucial to my survival to not panic. i scurry to unplug all electrical connections. fire fizzes out. i bet under 5 more minutes of that and the boat would have been gone, me and piña exploded for the seagulls.
i thankfully got to return the destroyed battery to westmarine as a defective and hazardous product. the 12ft. of 4gauge wire linking the starter battery to the beast AGMs melted inside and needed to be replaced. i took care of all that and now our electrical system is all upgraded and running fine.